DETAILED ACTION
Notice of Pre-AIA or AIA Status
The present application, filed on or after March 16, 2013, is being examined under the first inventor to file provisions of the AIA .
Response to Amendment
In Applicant’s response dated May 13, 2026, claims 1 and 5 are amended. Claims 6-9 are added. Claims 1-9 are pending and considered.
Status of Application
The Claim Interpretations as provided in the Office Action dated February 18, 2026 are maintained. The rejections set forth within the Office Action dated February 18, 2026 are modified as necessitated by Applicant amendments.
Claim Rejections - 35 USC § 103
The text of those sections of Title 35, U.S. Code not included in this action can be found in a prior Office action.
Claim(s) 1-3, 5-6, and 8 is/are rejected under 35 U.S.C. 103 as being unpatentable over Choi et al. US20180190985A1, as provided on the IDS dated 7/24/2023, hereinafter Choi.
Regarding Claim 1, Choi discloses an energy storage device [Choi abstract and throughout] comprising
a negative electrode including a negative substrate and a negative active material layer layered directly or indirectly on at least one surface of the negative substrate [Choi 0104 and throughout],
wherein the negative active material layer contains:
solid graphite particles that have a median diameter D1 [Choi abstract and throughout, fine second artificial graphite particles B with D1 of 3 µm to 5 µm. Choi does not teach voids in the fine second artificial graphite particles B; thus, Choi’s fine artificial graphite particles B are considered solid graphite particles meeting the requirements of the limitation.];
hollow graphite particles that have a larger median diameter D2 than the solid graphite particles [Choi abstract, 0020, 0023, 0025, 0052-0055, 0064-0066, 0095-0097, the first artificial graphite particles A, which are secondary particles, with D2 of 15 µm to 20 µm, Choi teaches first artificial graphite particles A include secondary particles having first pores inside the secondary particle [0020, 0052-0055], second pores as an empty space between the carbon coating layer and the graphite particle [0023, 0064-0066 ], and third pores as empty space between internal graphite particles and the second artificial graphite particle [0025, 0064-0066 ], which result in a porosity of 5 to 20% providing the function of improving contact area between lithium ions and the active material [0052-0055]. Choi’s pores as describe provide a functional empty space within the particles and thus read on hollow graphite particles as claimed. Since the size of Choi’s hollow graphite particles have a diameter range greater than the diameter range of the solid graphite particles, the medium diameter requirement is met. ]; and
a conductive agent, and wherein the conductive agent is fibrous carbon [Choi 0116, Choi discloses materials for a conductive agent which include carbon fibers], and
wherein a content ratio of the hollow graphite particles to the total content of the hollow graphite particles and the solid graphite particles is 10% by mass or more and 80% by mass or less [Choi 0157, Table 1, Choi teaches a comparative example 3 where the content ratio of the hollow graphite particles to the total content of the hollow graphite particles and the solid graphite particles is 82 % by mass, which is considered merely close to the claimed range. Thus, Choi’s example obviates the claimed range. Per MPEP 2144.05, in the case where the claimed ranges "overlap or lie inside ranges disclosed by the prior art" or are “merely close” a prima facie case of obviousness exists.]. Choi further teaches reduced preparation cost of the solid graphite particle (B) as compared to the hollow graphite particle (A), which would be considered a motivation for using more of the solid graphite particle [Choi 0089] if the required energy storage specifications for the specific application can be met. Choi further teaches that the reduced irreversible capacity and initial efficiency depends on particle and teaches selecting a particle size to lessen irreversible capacity and initial efficiency changes [Choi 0089-0091]. It would have been obvious to one of ordinary skill in the art before the effective filing date to select a content of hollow particles near 82% from Choi’s example, which is merely close to the claimed range as described above, for the predictable result of an energy storage device with sufficient capacity and efficiency for a specified application and reduced preparation cost [Choi 0089, 0157].
Regarding Claim 2, Choi discloses the energy storage device according to claim 1, wherein a relationship between the median diameter D1 of the solid graphite particles and the median diameter D2 of the hollow graphite particles satisfies 1 < (D2/D1) ≤ 10 [Choi abstract and throughout, 0139-0152, Table 1, D1 is 3 to 5 µm and D2 is 15 to 20µm in Table 1, Choi’s examples 1-5 are for mixing hollow artificial graphite particles (first artificial graphite particles) with solid graphite particles (second artificial graphite) with results provided in Table 1. Example 1 ratio is 20 µm/4µm or 4, Example 2 ratio is 19 µm/5µm or 3.8, Example 3 ratio is 15 µm/3µm or 5, Example 4 ratio is 20 µm/4µm or 5, Example 5 ratio is 20 µm/4µm or 5, Comparative Example 3 has a ratio of 20 µm/4µm or 5, all of which anticipate the claimed range].
Regarding Claim 3, Choi discloses the energy storage device according to claim 1 wherein the median diameter D1 of the solid graphite particles is 1 µm or more and less than 5 µm [Choi abstract and throughout, 0139-0152, Table 1, D1 is 3 to 5 µm, Choi’s examples 1-5 with solid graphite particles (second artificial graphite) summarized in Table 1. Example 1 4µm, Example 2 5µm, Example 3 3µm, Example 4 4µm, Example 5 4µm, Comparative Example 3 4µm, all of which anticipate the claimed range.], and the median diameter D2 of the hollow graphite particles is 5 µm or more and 20 µm or less [Choi abstract and throughout, 0139-0152, Table 1, D2 is 15 to 20 µm, Choi’s examples 1-5 with hollow graphite particles (first artificial graphite) summarized in Table 1. Example 1 20µm, Example 2 19µm, Example 3 15µm, Example 4 20µm, Example 5 20µm, Comparative Example 3 20µm, all of which anticipate the claimed range.].
Regarding claim 5, Choi discloses a negative electrode for an energy storage device [Choi abstract and throughout], comprising
a negative substrate and a negative active material layer layered directly or indirectly on at least one surface of the negative substrate [Choi 0104 and throughout],
wherein the negative active material layer contains:
solid graphite particles that have a median diameter D1 [Choi abstract and throughout, fine second artificial graphite particles B with D1 of 3 µm to 5 µm. Since Choi does not teach voids in the fine second artificial graphite particles B, the broadest reasonable interpretation of Choi is the fine artificial graphite particles B are solid graphite particles.];
hollow graphite particles that have a larger median diameter D2 than the solid graphite particles [Choi abstract, 0020, 0023, 0025, 0052-0055, 0064-0066, 0095-0097, the first artificial graphite particles A with D2 of 15 µm to 20 µm, Choi teaches first artificial graphite particles A have first pores inside the secondary particle [0020, 0052-0055], second pores as an empty space between the carbon coating layer and the graphite particle [0023, 0064-0066 ], and third pores as empty space between internal graphite particles and the second artificial graphite particle [0025, 0064-0066 ], which result in a porosity of 5 to 20% providing the function of improving contact area between lithium ions and the active material [0052-0055]. Choi’s pores as describe provide a functional empty space within the particles and thus read on hollow graphite particles as claimed. Since the size of Choi’s hollow graphite particles have a diameter range greater than the diameter range of the solid graphite particles, the medium diameter requirement is met. ]; and
a conductive agent, and wherein the conductive agent is fibrous carbon [Choi 0116, Choi discloses materials for a conductive agent which include carbon fibers],
wherein a content ratio of the hollow graphite particles to the total content of the hollow graphite particles and the solid graphite particles is 10% by mass or more and 80% by mass or less [Choi 0157, Table 1, Choi teaches a comparative example 3 where the content ratio of the hollow graphite particles to the total content of the hollow graphite particles and the solid graphite particles is 82 % by mass, which is considered merely close to the claimed range. Thus, Choi’s example obviates the claimed range. Per MPEP 2144.05, in the case where the claimed ranges "overlap or lie inside ranges disclosed by the prior art" or are “merely close” a prima facie case of obviousness exists.]. Choi further teaches reduced preparation cost of the solid graphite particle (B) as compared to the hollow graphite particle (A), which would be considered a motivation for using more of the solid graphite particle [Choi 0089] if the required energy storage specifications for the specific application can be met. Choi further teaches that the reduced irreversible capacity and initial efficiency depends on particle and teaches selecting a particle size to lessen irreversible capacity and initial efficiency changes [Choi 0089-0091]. It would have been obvious to one of ordinary skill in the art before the effective filing date to select a content of hollow particles near 82% from Choi’s example, which is merely close to the claimed range as described above, for the predictable result of an energy storage device with sufficient capacity and efficiency for a specified application and reduced preparation cost [Choi 0089, 0157].
Regarding Claim 6, Choi discloses the energy storage device of claim 1 [Choi abstract and throughout], wherein the content ratio of the hollow graphite particles to the total content of the hollow graphite particles and the solid graphite particles is 10% by mass or more and 75% by mass or less [Choi 0157, Table 1, Choi teaches a comparative example 3 where the content ratio of the hollow graphite particles to the total content of the hollow graphite particles and the solid graphite particles is 82 % by mass, which is considered merely close to the claimed range. Thus, Choi’s example obviates the claimed range. Per MPEP 2144.05, in the case where the claimed ranges "overlap or lie inside ranges disclosed by the prior art" or are “merely close” a prima facie case of obviousness exists.]. Choi further teaches reduced preparation cost of the solid graphite particle (B) as compared to the hollow graphite particle (A), which would be considered a motivation for using more of the solid graphite particle [Choi 0089] if the required energy storage specifications for the specific application can be met. Choi further teaches that the reduced irreversible capacity and initial efficiency depends on particle and teaches selecting a particle size to lessen irreversible capacity and initial efficiency changes [Choi 0089-0091]. It would have been obvious to one of ordinary skill in the art before the effective filing date to select a content of hollow particles near 82% from Choi’s example, which is merely close to the claimed range as described above, for the predictable result of an energy storage device with sufficient capacity and efficiency for a specified application and reduced preparation cost [Choi 0089, 0157].
Regarding Claim 8, Choi discloses the negative electrode of claim 5 [Choi abstract and throughout], wherein the content ratio of the hollow graphite particles to the total content of the hollow graphite particles and the solid graphite particles is 10% by mass or more and 75% by mass or less [Choi 0157, Table 1, Choi teaches a comparative example 3 where the content ratio of the hollow graphite particles to the total content of the hollow graphite particles and the solid graphite particles is 82 % by mass, which is considered merely close to the claimed range. Thus, Choi’s example obviates the claimed range. Per MPEP 2144.05, in the case where the claimed ranges "overlap or lie inside ranges disclosed by the prior art" or are “merely close” a prima facie case of obviousness exists.]. Choi further teaches reduced preparation cost of the solid graphite particle (B) as compared to the hollow graphite particle (A), which would be considered a motivation for using more of the solid graphite particle [Choi 0089] if the required energy storage specifications for the specific application can be met. Choi further teaches that the reduced irreversible capacity and initial efficiency depends on particle and teaches selecting a particle size to lessen irreversible capacity and initial efficiency changes [Choi 0089-0091]. It would have been obvious to one of ordinary skill in the art before the effective filing date to select a content of hollow particles near 82% from Choi’s example, which is merely close to the claimed range as described above, for the predictable result of an energy storage device with sufficient capacity and efficiency for a specified application and reduced preparation cost [Choi 0089, 0157].
Claim(s) 4 is/are rejected under 35 U.S.C. 103 as being unpatentable over Choi, as provided for claim 1 above, and further in view of Ogi et al. JP2018078029, as provided on the IDS dated 7/24/2023 (machine translation relied upon provided), hereinafter Ogi.
Regarding claim 4, Choi discloses the energy storage device according to claim 1 but is silent to wherein the fibrous carbon has an average aspect ratio of 50 or more and 100 or less. Ogi discloses a negative electrode for an energy storage device [Ogi 0001 and throughout] wherein fibrous carbon provides the function of being a conductive agent [Ogi 0022] and having an aspect ratio of 10 to 200, which overlaps and obviates the claimed range. Per MPEP 2144.05, in the case where the claimed ranges "overlap or lie inside ranges disclosed by the prior art" a prima facie case of obviousness exists. It would have been obvious to one of ordinary skill in the art before the effective filing date to combine Ogi’s teaching about aspect ratio for fibrous carbon with Choi’s battery with fibrous carbon as a conductive material for the predictable result of a battery with a negative electrode with good electrical conductivity [Choi 0116; Ogi 0029].
Claims 7 and 9 is/are rejected under 35 U.S.C. 103 as being unpatentable over Choi, as provided for claim 1 and 5 above, and further in view of Mabuchi et al. [US6156432A], hereinafter Mabuchi.
Regarding Claims 7 and 9, Choi discloses the energy storage device according to claim 1 (claim 7) and the negative electrode of claim 5 (claim 9) but teaches the hollow graphite particles are artificial graphite [Choi abstract and throughout] and is, therefore, silent to wherein the hollow graphite particles are natural graphite as required by the claims. Mabuchi teaches graphite particles for an anode [Mabuchi column 1 and throughout] for an energy storage device [Mabuchi column 1 and throughout, lithium battery] with a large number of cavities [Mabuchi column 3] formed internally in the graphite particles through intentionally formed pores for the purpose of improved discharge capacity [Mabuchi column 1]. Since the internal structure of Mabuchi’s graphite particles contains functional voids, Mabuchi’s particles as describe read on the claimed hollow graphite particles. Mabuchi further teaches the graphite particles can be natural graphite, artificial graphite, or graphitized carbon materials [Mabuchi column 3]. Thus, Mabuchi’s teaching of natural graphite particles makes natural graphite particles art recognized for use as hollow graphite particles for an anode per MPEP 2144.06. It would have been obvious to one of ordinary skill in the art before the effective filing date to combine Mabuchi’s teachings with the prior art of Choi and substituting hollow natural graphite particles for Choi’s artificial graphite particles for the predictable result of an energy storage device or negative electrode with the required capacity [Choi 0089; Mabuchi columns 1-2 and throughout].
Response to Arguments
With regard to Applicant’s arguments on pgs. 4-6 regarding the anticipation rejections, Applicant’s amendments are persuasive in overcoming the anticipation rejections over Choi provided in the Office Action dated February 18, 2026; thus, those rejections are withdrawn. However, claims 1-3, 5-6, and 8 are obvious over Choi as provided above. While the Examiner agrees that Choi teaches a content of hollow particles of 85 mass % or more, the Examiner respectfully disagrees that Choi’s teaching that “irreversible discharge capacity and initial efficiency may be reduced” is teaching away from the claimed range. Per MPEP 2123, "The use of patents as references is not limited to what the patentees describe as their own inventions or to the problems with which they are concerned. They are part of the literature of the art, relevant for all they contain." Disclosed examples and preferred embodiments do not constitute a teaching away from a broader disclosure or nonpreferred embodiments. While Choi teaches the irreversible discharge capacity and initial efficiency may be reduced, Choi does not teach that a lower content of hollow particles would render the energy storage device or the negative electrode inoperable. Further, the skilled artisan would understand that an energy storage device or negative electrode would have different requirements based on its application; therefore, reduced irreversible discharge capacity and initial capacity may not be significant for some applications. Further, Choi teaches an example where the content of hollow graphite particles is 82% as described above, which would be considered merely close to the claimed ranges of claims 1 and 5 per MPEP 2144.05 as described above. Even further, Choi provides a motivation for the use of the solid graphite particles due to cost [Choi 0089] and teaches controlling the particle size of the solid particles (B) to reduce the change in irreversible discharge capacity and initial capacity from using solid graphite particles (B) [Choi 0090].
Further, the Examiner has reviewed the instant specification for evidence of criticality of the claimed range. All of the examples in the instant specification are either 0%, 50%, or 100% hollow particles; therefore, there is no evidence of unexpected results or criticality of the claimed ranges of 10 to 80% (claims 1,5) or 10 to 75% (claims 6, 8).
Further, while the prior art of Mabuchi, provided for claims 7 and 9 above, was not relied upon for the rejections of claims 1, 5, 6, and 8, Mabuchi teaches the charge/discharge capacity can be increased by other process methods such as carbon coating [Mabuchi column 1-1], a process also taught by Choi [Choi 0043] and the instant specification [PGPub 0041], which is considered relevant to Applicant’s arguments.
With regard to Applicant arguments on pg. 6 regarding new claims 7 and 9, Choi in view of Mabuchi was found to obviate those claims for the reasons provided above.
For the reasons provided above, evidence of obviousness over the prior art outweighs evidence of novelty and nonobviousness of the instant invention.
Conclusion
Applicant's amendment necessitated the new ground(s) of rejection presented in this Office action. Accordingly, THIS ACTION IS MADE FINAL. See MPEP § 706.07(a). Applicant is reminded of the extension of time policy as set forth in 37 CFR 1.136(a).
A shortened statutory period for reply to this final action is set to expire THREE MONTHS from the mailing date of this action. In the event a first reply is filed within TWO MONTHS of the mailing date of this final action and the advisory action is not mailed until after the end of the THREE-MONTH shortened statutory period, then the shortened statutory period will expire on the date the advisory action is mailed, and any nonprovisional extension fee (37 CFR 1.17(a)) pursuant to 37 CFR 1.136(a) will be calculated from the mailing date of the advisory action. In no event, however, will the statutory period for reply expire later than SIX MONTHS from the mailing date of this final action.
Contact Information
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/M. T. LEONARD/Examiner, Art Unit 1724
/STEWART A FRASER/Primary Examiner, Art Unit 1724
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